Propellable apparatus and related methods

ABSTRACT

Propellable apparatus, assemblies and related methods including a self-enclosed member are disclosed. The self-enclosed member can include an inner surface at least partially defining an enclosed region, and an outer surface that turns outwardly to engage a cavity or lumen wall in addition to turning inward to at least partially encompass a central region defining a longitudinal path. The apparatus can include an internal drive mechanism engageable with the outer surface of the self-enclosed member to provide relative movement between the self-enclosed member and the cavity or lumen wall. A tapered member, positioned on the apparatus adjacent an end of the self-enclosed member, can provide a size transition between an outer surface portion of the self-enclosed member and an outer surface of a payload insertable within the central region. In some examples, one or more reinforcing members can be integrated within the self-enclosed member for increased durability and rotational use.

CLAIM OF PRIORITY

This non-provisional application claims the benefit of priority under 35U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No.61/152,780 filed on Feb. 16, 2009, entitled “PROPELLABLE APPARATUS ANDRELATED METHODS,” the specification of which is herein incorporated byreference in its entirety.

TECHNICAL FIELD

This patent document pertains generally to an apparatus configured tofacilitate carrying a payload. More particularly, but not by way oflimitation, this patent document pertains to a propellable apparatusconfigured to facilitate carrying a payload, such as an endoscope orother instrument, into a body or non-body cavity or lumen.

BACKGROUND

An endo scope is an instrument often used in medical procedures to viewa location of interest within a subject's body and transmit such view(s)to a caregiver or other observer. Endo scopes can also be used toperform a variety of diagnostic and interventional procedures, such asbiopsies and other small surgical procedures. Examples of endo scopesinclude a colono scope configured for use within the colon, an enteroscope configured for use within the stomach or small bowel, and abronchoscope configured for use within the trachea or bronchi. Endoscopes are typically inserted into body cavities or lumens via a naturalbodily orifice, but can also be inserted via a surface incision to gainaccess to the internal location of interest.

OVERVIEW

One approach in facilitating advancement of an endo scope or othersimilar payload instrument into, within, and out of a cavity or lumenincludes using a propellable apparatus, such as described in Ziegler etal. U.S. Pat. No. 6,971,990, entitled “PROPULSION MECHANISM FORENDOSCOPIC SYSTEMS;” Ziegler et al. U.S. Patent Application PublicationNo. 2006/0089533, entitled “SELF-PROPELLABLE APPARATUS AND METHOD;”Ziegler et al. U.S. Patent Application Publication No. 2008/0045790,entitled “SELF-PROPELLABLE ENDOSCOPIC APPARATUS AND METHOD;” SheridanU.S. Patent Application Publication No. 2009/0233747, entitled“TORQUE-ADJUSTING DRIVE MECHANISM FOR A DEVICE;” Allen et al. U.S.Patent Application Publication No. 2009/0227838, entitled “PROPELLABLEAPPARATUS WITH PASSIVE SIZE CHANGING ABILITY;” and Eidenschink et al.U.S. Patent Application No. 61/243,208, entitled “PROPELLABLE APPARATUSWITH ACTIVE SIZE CHANGING ABILITY,” the disclosures of each of which areherein incorporated by reference in their entirety, including theirdescriptions of a propellable apparatus and related methods.

In various examples, a drive structure including one or more drivemembers and gear or wheel power couplings can be mounted on theendoscope or other payload instrument. The drive structure can propel aself-enclosed member (e.g., self-enclosed tube, such as a toroidialmembrane, or self-enclosed strips) to create propulsion force against acavity or lumen wall. This propulsion force can aid in advancing orwithdrawing the endoscope or other payload instrument relative to acavity or lumen wall.

In some examples, the propellable apparatus comprises a permeableself-enclosed member; while in other examples, the propellable apparatuscomprises an impermeable self-enclosed member. The self-enclosed membercan be sized and shaped to fit within and engage a cavity or lumen wall.The self-enclosed member can comprise an inner surface defining anenclosed region, and an outer surface that turns outward to engage thecavity or lumen wall in addition to turning inward to encompass acentral region defining a concentric longitudinal path. An attachmentcan be coupled to the self-enclosed member. The attachment can beconfigured to secure engagement between an endoscope or other payloadinstrument and the self-enclosed member. The self-enclosed member can bepowered to provide movement relative to the cavity or lumen wall. Thiscan help move the payload, with respect to the cavity or lumen, in atleast one of a forward or reverse direction with respect to the definedlongitudinal path.

Various options for the above-referenced propellable apparatus areavailable, each of which can be beneficial in certain applications andcircumstances. In some examples, the attachment between the propellableapparatus and the payload is made at a front-end tip portion of thepayload. This can be advantageous for advancing the payload throughsharp bends in a body cavity or lumen. In some examples, the propellableapparatus can be made to have a relatively short length (e.g., betweenabout 0.8 inches and about 1.5 inches) so-as-to not limit thearticulation of a payload, having a separately controllable articulatingcapability, when it is mounted at or near the front-end thereof. In someexamples, the one or more drive members can be made of flexible cablesincluding wrapped filaments instead of solid wire to allow greaterflexing of the drive members without reaching unacceptable internalstress levels. In some examples, an additional component such as a wipercan be added to at least one end of the propellable apparatus, therebyshielding tissue from the apparatus drive mechanism. In some examples, atapered member (e.g., a wedge-shaped member) can be added behind thepropellable apparatus to provide a size transition from the outersurface of the payload to the larger diameter, outer surface of theself-enclosed member (e.g., tube), thereby easing withdrawn of theapparatus from the cavity or lumen. The tapered member can be passivelyor actively (e.g., actuatably) expanded and contracted, as needed or asdesired. In some examples, different reinforcing members may be used forthe rotating, self-enclosed member to improve its durability androtational use.

To better illustrate the present propellable apparatus, a non-limitinglist of examples is provided here:

In Example 1, a propellable apparatus comprises a self-enclosed memberconfigured to fit within and partially engage a cavity or lumen wall,the self-enclosed member including an inner surface at least partiallydefining an enclosed region, and an outer surface that turns outwardlyto engage the cavity or lumen wall in addition to turning inward to atleast partially encompass a central region defining a longitudinal path;an internal drive mechanism engageable with the outer surface of theself-enclosed member, thereby providing relative movement between theself-enclosed member and the cavity or lumen wall; and a tapered memberpositioned adjacent an end of the self-enclosed member, the taperedmember providing a size transition from the end of the self-enclosedmember to a diametrically smaller, outer surface of a payload insertablewithin the central region.

In Example 2, the propellable apparatus of Example 1 is optionallyconfigured such that the tapered member is actively expandable orcontractible.

In Example 3, the propellable apparatus of Example 2 is optionallyconfigured such that the tapered member comprises a conically-shaped,actively inflatable balloon.

In Example 4, the propellable apparatus of Example 3 optionallycomprises one or more tubular members configured to move a fluid into orout of the inflatable balloon for size adjustment use.

In Example 5, the propellable apparatus of any one or any combination ofExamples 1-4 is optionally configured such that the inflatable balloonincludes at least one groove configured to house one or more elongate ortubular members (e.g., elongate drive members engagable with theinternal drive mechanism or tubular members configured to move the fluidinto or out of the inflatable balloon).

In Example 6, the propellable apparatus of any one or any combination ofExamples 1-5 is optionally configured such that the tapered memberincludes a wedge-like cross-sectional shape when viewed in alongitudinal direction.

In Example 7, the propellable apparatus of any one or any combination ofExamples 1-6 is optionally configured such that the tapered member iscoupled adjacent a back-end of the self-enclosed member.

In Example 8, the propellable apparatus of any one or any combination ofExamples 1-7 optionally comprises one or more wiper members including anedge configured to press against the outer surface of the self-enclosedmember, thereby removing debris as the self-enclosed member turnsinward.

In Example 9, the propellable apparatus of Example 8 is optionallyconfigured such that the edge of the one or more wiper members includesa lubricious coating.

In Example 10, the propellable apparatus of any one or any combinationof Examples 1-9 optionally comprises an attachment coupled in proximityto the self-enclosed member, the attachment configured to couple thepayload within the central region.

In Example 11, the propellable apparatus of Example 10 is optionallyconfigured such that the payload longitudinally extends from a handleportion to a leading viewing portion, and wherein the self-enclosedmember is attached at the leading viewing portion.

In Example 12, the propellable apparatus of any one or any combinationof Examples 10 or 11 is optionally configured such that the payload isan endo scope.

In Example 13, the propellable apparatus of any one or any combinationof Examples 1-12 optionally comprises one or more drive membersconfigured to transmit externally-generated power to the internal drivemechanism, and wherein the one or more drive members include a pluralityof filaments wound in at least a first direction and a second direction,the second direction different than the first direction.

In Example 14, the propellable apparatus of any one or any combinationof Examples 1-13 is optionally configured such that the internal drivemechanism is configured to receive power in a first form and convert thefirst form power to a linear impelling power received by theself-enclosed member.

In Example 15, the propellable apparatus of Example 14 is optionallyconfigured such that the internal drive mechanism includes a worm gearlocated at least partially within the central region, the worm gear,when powered, configured to impart the linear impelling power to theself-enclosed member via a motive drive wheel or gear.

In Example 16, the propellable apparatus of Example 15 is optionallyconfigured such that the worm gear is coupled to a mechanical powertransmission providing a spinning mechanical power, the worm gearconfigured to partially convert the spinning mechanical power to thelinear impelling power.

In Example 17, the propellable apparatus of any one or any combinationof Examples 1-16 is optionally configured such that a longitudinallength of the apparatus is less than about 1.5 inches, less than about1.4 inches, less than about 1.3 inches, less than about 1.2 inches, lessthan about 1.1 inches, or less than about 1.0 inches, such that theapparatus length is less than a length of a payload's rigid front-endtip portion.

In Example 18, a propellable apparatus comprises a self-enclosed membersized and shaped to fit within and engage a cavity or lumen wall, theself-enclosed member including an inner surface at least partiallydefining an enclosed region, and an outer surface that turns outwardlyto engage the cavity or lumen wall in addition to turning inward to atleast partially encompass a central region defining a longitudinal path;and at least one reinforcing member embedded between the inner surfaceand the outer surface of the self-enclosed member.

In Example 19, the propellable apparatus of Example 18 is optionallyconfigured such that the at least one reinforcing member includes astiffness or a toughness greater than a stiffness or toughness of theself-enclosed member. The reinforcing member can have a reduced axialelasticity as compared to the surrounding material of the self-enclosedmember. Optionally, the reinforcing member can include a meshconfiguration to yield relative inelasticity in a direction of rotationwith relatively high flexibility in bending.

In Example 20, the propellable apparatus of any one or any combinationof Examples 18 or 19 optionally comprises an internal drive mechanismengageable with the outer surface of the self-enclosed member, therebyproviding relative movement between the self-enclosed member and thecavity or lumen wall.

In Example 21, the propellable apparatus of Example 20 is optionallyconfigured such that the internal drive mechanism includes one or moregears or wheels, and wherein the at least one reinforcing member ispositioned in line with a position of the one or more gears or wheels.

In Example 22, the propellable apparatus of Example 21 is optionallyconfigured such that the outer surface of the self-enclosed memberincludes one or more tread sections configured to engage with the one ormore gears or wheels of the internal drive mechanism.

In Example 23, the propellable apparatus of any one or any combinationof Examples 18-22 is optionally configured such that the at least onereinforcing member includes at least one of a peek, a nylon, a polyesteror a urethane material.

In Example 24, the propellable apparatus of any one or any combinationof Examples 18-23 is optionally configured such that the at least onereinforcing member is molded into the self-enclosed member.

In Example 25, a propellable apparatus comprises means for providing aninner surface and an outer surface which move in opposite directionswhen the apparatus is in motion, including providing a self-enclosedmember defining a central cavity and having an enclosed region, which isconfigurable to enter into and navigate a cavity or lumen; means forproviding a tapered size transition between a member disposable with thecentral region and an outer surface portion of the self-enclosed member;means for reinforcing a stiffness or toughness of the self-enclosedmember; and means for propelling the self-enclosed member using theouter surface.

In Example 26, the propellable apparatus of Example 25 is optionallyconfigured such that the means for reinforcing includes means fordecreasing driving force transmission loss to the self-enclosed member,when powered.

In Example 27, the apparatus of any one or any combination of Examples1-26 is optionally configured such that all elements or options recitedare available to use or select from.

These and other examples, advantages, and features of the presentpropellable apparatus, assemblies and related methods will be set forthin part in following Detailed Description. This Overview is intended toprovide an introduction to the subject matter of the present patentdocument. It is not intended to provide an exclusive or exhaustiveexplanation of the invention. The Detailed Description is included toprovide further information about the present patent document.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, like numerals can be used to describe similarcomponents throughout the several views. Like numerals having differentletter suffixes can be used to represent different instances of similarcomponents. The drawings illustrate generally, by way of example, butnot by way of limitation, various propellable apparatus embodimentsdiscussed in the present document.

FIG. 1 illustrates an example of a cross-sectional view of a propellableapparatus and a payload, as constructed in accordance with at least oneassembly embodiment.

FIG. 2 illustrates an example of an attachment position between apropellable apparatus and a payload, as constructed in accordance withat least one assembly embodiment.

FIG. 3 illustrates an example of a cross-sectional view of a propellableapparatus, including a tapered-member, and a payload, as constructed inaccordance with at least one assembly embodiment.

FIG. 4 illustrates an example of an isometric view of a wiper memberpositionable at an end of a propellable apparatus, as constructed inaccordance with at least one embodiment.

FIG. 5 illustrates an example of a cross-sectional view of a propellableapparatus, including a back-end positioned wiper and tapered member, anda payload, as constructed in accordance with at least one assemblyembodiment.

FIG. 6 illustrates an example of an isometric view of a propellableapparatus, including an actively expandable and contractible taperedmember positioned at an apparatus back-end, associated drive members,and inflation/deflation tubes, as constructed in accordance with atleast one embodiment.

FIG. 7 illustrates an example of a schematic view of a propellableapparatus, including a back-end positioned tapered member mounted via awiper member, and a payload, as constructed in accordance with at leastone assembly embodiment.

FIG. 8 illustrates an example of a cross-sectional view of aself-enclosed member, as constructed in accordance with at least oneembodiment.

FIG. 9 illustrates an example of a cross-sectional view of aself-enclosed member including a reinforcing member, as constructed inaccordance with at least one embodiment.

DETAILED DESCRIPTION

The present inventors have recognized, among other things, that avariety of challenges are faced in the area of endoscope advancementthrough body cavities or lumens. Traditional endoscopes, for example,include a rigid or semi-rigid rod or shaft, which can be inserted into anatural orifice or incision and forced through the associated bodycavity or lumen to the location of interest. However, when a body cavityor lumen pathway is constricted, convoluted or consists of many curves,as can be the case with the colon, the stomach or small bowel, it can bedifficult or impossible to forcibly push the endoscope to the desiredlocation(s). In addition, the increased force required in traversingthrough each additional turn or corner of the cavity or lumen pathwayraises the risk of subject surgical complications, such as bowelperforation and patient discomfort and pain experienced during or aftera procedure.

The present inventors have also recognized that in a field differentfrom medical applications, optical or other payload instruments can beused in non-medical commercial and industrial applications to obtainviews, for example, from non-body cavity or lumens, such as sections ofpipe or other structures having a number of curves and turns. Suchnon-body cavity or lumens can be partially occluded or have build-up onan inner surface and thus present an irregular internal shape ordiameter impeding advancement of the viewing or other payloadinstruments.

One promising approach to endoscope or other payload instrumentadvancement through a body or non-body cavity or lumen can be apropellable apparatus configured to help advance the endoscope or otherpayload instrument through constricted, convoluted or curved pathways.To this end, the present inventors have recognized that (1) it cansometimes be advantageous to attach the propellable apparatus at afront-end tip portion of a payload, (2) a propellable apparatus having arelatively short length (e.g., between about 0.8 inches and about 1.5inches) does not limit articulation of a flexible payload, having aseparately controllable articulating capability, an appreciable degreewhen it is mounted at or near the front-end thereof, (3) drive membersmade of flexible cable including wrapped filaments allows for adequateflexing without reaching unacceptable internal stress levels duringrotation, (4) one or more wiper members can be added to the propellableapparatus, such as at one or both apparatus ends, to prevent tissue fromengaging with the apparatus drive mechanism, (5) a tapered member can beadded to a back-end of the propellable apparatus to facilitate removalof the apparatus from a cavity or lumen, and (6) one or more reinforcingmembers can be integrated within a self-enclosed member for increaseddurability and rotational use.

As shown in FIG. 1, a propellable apparatus 100 can comprise aself-enclosed member 102 (e.g., self-enclosed tube, such as a toroidialmembrane, or self-enclosed strips), which is sized and shaped to fitwithin and engage a cavity or lumen wall and be attachable to a payload104 (e.g., an endoscope or other instrument). Rotation of theself-enclosed member 102 can create a propulsive force against thecavity or lumen wall. In various examples, power to actuate theself-enclosed member can be generated outside the cavity or lumen and betransmitted to the self-enclosed member 102 via one or more elongatedrive members 106. At or near the self-enclosed member 102, the elongatemembers 106 can engage with one or more internal drive mechanisms 108(e.g., one or more worm gears or motive drive wheels), which in turn canbe engaged with an outer surface 110 of the self-enclosed member 102 asit passes through its smaller internal diameter 112. This allows theself-enclosed member 102 to engage the cavity or lumen wall as ittravels through its larger diameter 114. In various examples, one ormore rollers or skids 116 can be used to bias portions of theself-enclosed member 102 against an alternating sequence of peaksseparated by respective grooves of one or more gears or wheels of theinternal drive mechanisms 108.

In some examples, as shown in FIG. 2, it has been found advantageous toattach a propellable apparatus 100 at a front-end tip portion 202 of apayload 104. Mounting the propellable apparatus 100 at the front-end tipportion 202 of the payload 104 can have advantages in some bodyanatomies for gathering lumen tissue, for example, over the tip of anendoscope and helping the endoscope tip navigate through sharp folds ornarrowing diameters in a body cavity or lumen.

This mounting location can be advantageous in tortuous cavities orlumens, as compared to mounting the propellable apparatus 100 furtherback on the payload 104 behind an articulating section 204. Thereasoning behind this is that the tissue of the cavity or lumen wallwill have some drag against the tip of the payload 104, and this dragtypically increases as the tip is flexed more for tortuous anatomy. Ifthis drag over the tip is greater than the force with which theself-enclosed member 102 is acting to draw tissue over the propellableapparatus 100, then the apparatus 100 may fail to gather tissue over thetip of the payload 104. Conversely, if the propellable apparatus 100 ismounted at the front-end tip portion 202 of the payload 104, there canbe little to no drag in front of the apparatus 102 resisting therotating, self-enclosed member's 102 effect on the gathering of walltissue over the tip of the payload 104.

Mounting the propellable apparatus 100 at the front-end tip portion 202of the payload 104 can, however, put demands on the propellableapparatus 100, which are not present if the apparatus 100 is mountedbehind the payload's articulating, steerable section 204. The ends ofendoscopes, for example, have flexible steerable sections that aphysician can deflect using controls on a handle of the endoscope. Onechallenge of mounting the propellable apparatus 100 on the front-end tipportion 202 of the payload 104 is to not inhibit the physician's abilityto control the articulation of the payload tip. The articulating section204 of a scope is typically about 3 inches long and is locatedimmediately adjacent an about 1 inch rigid section 206 at the tip whichhouses the scope's optics. To not inhibit the articulation anappreciable degree, the propellable apparatus 100 can be mounted on therigid section 206 at the front-end tip portion 202 and the propellableapparatus 100 length can be about 1 inch in length, in some examples,for scopes having these typical dimensions. In other examples, thepropellable apparatus 100 length can be less than about 1.5 inches, lessthan about 1.4 inches, less than about 1.3 inches, less than about 1.2inches, less than about 1.1 inches, or less than about 1.0 inches, suchthat the apparatus length is less than a length of a rigid section 206located at or near a front-end tip 202 of a payload 104. These lowerlimits can be advantageous for small bowel and other applications whererelatively smaller and more articulatable payloads may be used. Anexample of a propellable apparatus 100 meeting this desired length isshown in the cross-sectional side view of FIG. 3. As compared to FIG. 1,it can be seen that the internal drive mechanisms 108 and opposing oneor more rollers or skids 116 have been compressed in their spacing toyield a shorter overall apparatus 100 length.

A second aspect of mounting the propellable apparatus 100 at thefront-end tip portion 202 of the payload 104 is that the articulatingsection 204 of the payload 104 is able to flex to a smaller radius ofcurvature 208 than the radius of curvature 210 of the body of thepayload 104 behind the articulating region 204 (see, FIG. 2). In sometypical colonoscopes, the radius of curvature at maximum flexing isabout 1 inch for the articulating section and about 2 inches for thebody of the scope. This can have implications for the apparatus elongatedrive members 106 if the propellable apparatus 100 is mounted at thefront-end tip portion 202 of the payload 104, as these drive members 106may need to tolerate a smaller radius of curvature in use when theapparatus 100 is mounted at the front-end tip portion 202 of the payload104 relative to being mounted behind the articulating section 204.

Rotating drive members 106 are subjected to oscillating stresses whenthey are flexed during rotation. These oscillating stresses can resultin fatigue failure of the drive members 106, if the stresses are highenough. These stresses increase as the radius of curvature decreases fora given drive member 106 design. For this reason, it may be desirable touse drive members 106 that operate at lower oscillating stresses for agiven radius of curvature when the propellable apparatus 100 is to bemounted at the front-end tip portion 202 of the payload 104.

One possible way of reducing the stresses due to bending is to use oneor more smaller diameter drive members 106. The smaller diameter candecrease the stresses due to bending, however, the smaller diameter canalso decrease the amount of torsional load the wire can carry. A secondpossible way to decrease the stresses in the drive members 106 due tobending can be to use a cable including wound filaments for each of thedrive members 106 instead of a solid wire. Drive cables may be produced,for example, by winding small diameter filaments in a helical patternaround a central wire in a first direction, and further winding moresmall diameter filaments around the outside of the first helically woundfilaments in a second, opposite direction. Additional small diameterfilaments can further be wound over the opposite direction filaments, asneeded or as desired. Having the helical filaments wound in more thanone direction allows the resulting cable to transmit torque in bothrotational directions without unacceptable unwinding of the woundfilaments. Due to the smaller diameter of the individual filaments used,the drive members 106 can tolerate a smaller radius of curvature ascompared to solid drive wires. This can allow use of a larger diametercable than a solid drive wire for a given application. This can furtherprovide greater flexibility in meeting both torsional and fatiguerequirements for the one or more drive members 106.

When mounting a propellable apparatus 100 at the front-end tip portion202 of a payload 104, a cable including small diameter filaments can beuse for the entire length of the one or more drive members 106. A cableincluding small diameter filaments can also be used in a composite drivemember 106 construction with the cable including filaments used for thelength along the articulating section 204 of the payload 104 and a soliddrive wire behind the articulating section 204 where the bending radiusrequirements are decreased. A composite drive member construction can bedesirable to minimize propellable apparatus manufacturing costs, as thecable construction is likely to be more expensive than the solid drivewire. One example of a solid wire drive wire for a propellable apparatus100 application is a straightened 400 kpsi stainless steel 0.022 inchdiameter wire. One example of a cable including filaments that can beused for a propellable apparatus 100 application is a 0.050 inch cableproduced by SS White® Technologies, Inc. of Piscataway, N.J., whichincludes four wires wrapped around a central wire and two sets of sixwires wound around the four wires in an opposite direction. All of theseindividual filaments, in this example, are 0.007 inches in diameter.

A third challenge of mounting the propellable apparatus 100 at thefront-end tip portion 202 of the payload 104 is that heat can build upat the tip. Endoscopes, for example, can include small lights at theirtips projecting forward to allow the physician to see down a cavity orlumen with the optics mounted at the tip. These lights generate heat andthis heat should be dissipated. If the heat were to build up and thetemperature of the tip became excessively high, it can possibly degradethe image quality of the optics. It could also become a risk of damagingcavity or lumen wall bodily tissue that contacts the heated end of thescope.

Mounting the propellable apparatus 100 over the front-end tip portion202 of the payload 104 could help insulate the tip, limiting the heatdissipation to adjacent bodily tissue. Additionally, the one or moregear power couplings 108 and drive members 206 interface could generateadditional heat of its own. Thus, in some embodiments, it may bedesirable to control the heat generated by the internal drive mechanisms108 of the propellable apparatus 100. This can be done by, for example,minimizing the drive power input to the propellable apparatus 100 neededby minimizing the drag of the self-enclosed member 102 as it rotates. Tothis end, lubricious materials and coatings for the contact surfaces andthe self-enclosed member 102 itself can be added. Heat reduction canalso be addressed using a small amount of cooling water introducedinside the propellable apparatus 100. In one example, the cooling watercan be introduced through a tubular member in the one or more drivemembers 106 (see, FIG. 3), which exits inside the propellable apparatus100 in the internally-positioned drive mechanism 108 or in a lumen 302between the propellable apparatus 100 and the payload surface.

In various examples, such as are shown in FIGS. 1, 3, 4, 5 and 7, thepropellable apparatus 100 can include a wiper member 402. The presentinventors have found that, in practice, it should be assured that bodilytissue or other cavity or lumen debris is not pulled via theself-enclosed member 102 into the internally-positioned drive mechanisms108 as the self-enclosed member 102 rotates into its small diameter path112 (see, FIG. 1). In FIG. 1, a wiper member 402 is shown mounted to aportion of the internal drive mechanism 108, with an edge 404 pressingagainst the self-enclosed member 102 as it passes into its smallerdiameter 112 path. In various examples, the wiper member 402 is acomponent that can be added to the propellable apparatus 100 assembly toprevent or inhibit tissue or other cavity or lumen debris from beingpulled into the internal mechanisms of the apparatus 100 by therotating, self-enclosed member 102. The wiper member 402 can act like asqueegee to separate any tissue or other debris from sticking to anouter surface of the self-enclosed member 102. One example of anisometric view of a wiper member 402 is shown in FIG. 4.

As shown in FIG. 5, the wiper member 402 can also be placed against theouter surface 110 of the self-enclosed member 102 at or near its largerouter diameter 114. In various examples, the wiper member 402 can berigid and shaped to substantially match the contour of the outer surfaceof the self-enclosed member 102, or it can be flexible and conform tothis outer surface. The wiper member 402 can be made of a wide range ofengineering polymers or metals. In one example, the wiper member 402 ismade from Santoprene®281 having a 55 MED durometer. In some examples,the wiper member 402 is made of a relatively lubricious polymer (e.g.,fluoropolymers) to minimize the drag it adds to the rotation of theself-enclosed member 102. In some examples, the wiper member 402 iscoated with a lubricious material, such as silicone oil or a hydrophiliccoating.

In various examples of the propellable apparatus 100, such as theapparatus shown in FIG. 1, the back-end 502 includes a fairly abruptdiameter change 504 between the outer diameter 114 of the self-enclosedmember 102 and a diameter of the payload 104 located behind it. In someexamples, it can be desirable to have this diameter change 504 tapermore gradually, such that there are few to no ledges to catch bodilytissue or other debris on as the propellable apparatus 100 is beingwithdrawn through a cavity or lumen. It may also be desirable to havethe rigid length of the propellable apparatus 100 as short as possibleto ease advancement through tortuous anatomy and to not inhibit payload104 articulation when the propellable apparatus 100 is mounted on thefront-end tip portion 202 of an articulating payload, such as anendoscope.

It may be further desirable to have a tapered member (e.g., awedge-shaped member) 506 that does not hinder the effectiveness of anypropellable apparatus 100 components, such as the various wiper membersdiscussed above. In one example, as shown in FIG. 6, the tapered member506 is in the form a conically-shaped, actively inflatable balloon 602,which is sleeved over a portion of a payload 104 behind the propellableapparatus 100. In this way, the balloon 602, when inflated, creates asmooth tapered diameter transition from the back-end 502 of the rotatingmembrane to the surface of the payload 104. This inflatable balloon 602can be attached to the back-end 502 of the propellable apparatus 100such that its position relative to the back-end 502 is fixed. In someexamples, one or more tubular members 604 to inflate or deflate theballoon can be included in the casing of the one or more drive members106 of the propellable apparatus 100. In practice, this balloon 602 canbe un-inflated and collapsed or otherwise contracted when the scope isbeing advanced forward in a cavity or lumen, assisted by the propellableapparatus 100 and its rotating, self-enclosed member. After reaching atarget point in the cavity or lumen, such as the cecum duringcolonoscopy, the rotation of the self-enclosed member 102 can be stoppedand the balloon can be 602 inflated. The payload 104 can then bewithdrawn through the cavity or lumen as the operator (e.g., physician)does his/her inspection. It is believed that the presence of anactivatable (e.g., actuatable) tapered member 506, such as the balloon602, can minimize drag in the cavity or lumen when in a deflated stateduring advancement, and minimize risk of tissue or other debris hang upduring withdrawal when in an expanded state.

Other options for the tapered member 506, and particularly the balloon602, can be as follows. The balloon 602 can be made to be flexible sothat it does not inhibit any desired flexing of the payload 104 beneathit. This could be valuable when the propellable apparatus 100 is mountedat the front-end tip portion 202 of the payload 104 and the balloon 602,at least in part, is mounted over the payload's articulating section 204(see, FIG. 2). In one example, the balloon 602 is formed from sheeturethane having a durometer of about 80 A and a thickness of about 0.003inches. The sheet urethane can be cut and heat sealed into a conicalballoon shape having a diameter at one end approximately equal to thediameter of the rotating, self-enclosed member 102 of the propellableapparatus 100. The balloon 602 can be sealed down at its base to acylindrical urethane tube having a diameter slightly larger than thediameter of the payload 104 it is sliding or otherwise advancing over. Agroove 606 can be formed in the conical or otherwise shaped balloon 602,such as by heat sealing the balloon down to the urethane tube in oneline along the length of the balloon 602. This groove 606 can act as apath for the one or more drive members 106 powering the rotatingpropellable apparatus 100 or the one or more tubular members 604 used toinflate or deflate the balloon 602. In some examples, the actualinflation and deflation of the balloon 602 can be done with a syringeand a stop cock on the end of the inflation tubular members 604 off thedrive members 106, at or near their connection 608 to a motorcontroller.

In another example, as shown in FIG. 7, the tapered member 506 isachieved with a flexible polymer component 702 fixedly mounted to thepropellable apparatus 100, such as via a wiper member 402. In thisexample, the tapered member 506 is passive and does not requireactuation on the part of the operator (e.g., physician). The taperedmember 506 of FIG. 5 shows a second variation of this approach. In someexamples, as shown in FIG. 7, the tapered member 506 including aflexible polymer component 702 is connected behind the wiper member 402and leaves clearance 704 off of the rotating, self-enclosed member 102to minimize the risk of creating a tissue or other debris pinch point.In FIG. 5, the wiper member 402 is integrated into the tapered backpiece 506 and has the wiper edge 404 on the outer surface of therotating, self-enclosed member 102.

In various examples, as shown in FIGS. 8 and 9, the propellableapparatus 100 includes a self-enclosed member 102 having one or more ofa thicker walled section 804, a tread 802, or a reinforcing member 902.In various examples, the self-enclosed member 102 can be configured todecrease transmission loss thereto of the driving forces provided by theinternal drive mechanisms 108. In some examples, at least a portion ofthe outer surface of the self-enclosed member 102 can include a tread802 having an alternating sequence of peaks separated by respectivegrooves (e.g., teeth), which are configured to engage with thealternating peaks and grooves of one or more gears or wheels of theinternal drive mechanisms 108 (see, FIG. 1). As shown in FIG. 1, thesegears or wheels may be engaged against the tread by biasing rollers orskids 116 positioned inside the self-enclosed member 102.

In use, the gears of the drive mechanisms 108 may skip or slip over thetreads in the surface of the self-enclosed member 102 if enoughrotational drag is placed on the member 102. This skipping or slippingcan also occur if the self-enclosed member 102 has a smooth surface(e.g., without a tread). In addition, the skipping or slipping can getworse if the self-enclosed member 102 is relatively more elastic and canstretch as a result of increased rotational drag on the member 102.Minimizing the skipping or slipping of the self-enclosed member 102 overthe gears can be desirable both for repeatable performance and becausethe skipping or slipping can accelerate the wear of the member 102 onthe gears.

Engagement between the self-enclosed member 102 and the gears or wheelsof the internal drive mechanisms 108 can be improved by having higherpressure between the rollers or skids 116 and the gears or wheels sothat the member 102 is held tighter against the gears or wheels. Even ifno skipping occurs, there can be a degree of wear on the self-enclosedmember 102 by the gear or wheel contacting the teeth in normal use. Asthe wear on the self-enclosed member 102 advances, the member 102 outersurface can become cut and develop frayed edges on these cuts. Thiscutting and fraying can further decrease the engagement of the gears orwheels of the internal drive mechanism 108 and the self-enclosed member102 until the member 102 slows and eventually stalls or the frayed endsbecome wrapped in the gear or wheel coupling and abruptly stalls theapparatus 100. Thus, FIG. 9 illustrates one way of reinforcing theself-enclosed member 102 to significantly increase its wear resistanceand significantly decrease its elasticity, thereby improving itsrotational and overall performance.

FIG. 8 illustrates a cross-sectional view of one example of aself-enclosed member 102 for use in a propellable apparatus 100. In thissectional example, the self-enclosed member 102 is shown as a cylinderin an intermediate state during manufacture, before it is rolled into atoroid and seamed to itself. The self-enclosed member 102 can be made ofa polymer such as a urethane (e.g., Stevens Urethane 1880 having adurometer of about 80-85 A, and produced by Stevens Urethane ofEasthampton, Mass.). Urethanes are generally tough polymers with goodflexibility, and this combination makes them adequate candidates for theself-enclosed member 102 material.

FIG. 9 illustrates a cross-sectional view of another example of aself-enclosed member 102 having a reinforcing member 902 (e.g.,reinforcing mesh) embedded in the member 102 wall. As shown, theself-enclosed member 102 of this example includes three thicker walledsections 804 around its circumference with treads 802 in the sections804 to match up and align with the gears or wheels of the internal drivemechanism 108 at three locations, for example, around the circumferenceof the propellable apparatus 100. In this reinforcing example, areinforcing member 902 is embedded in the sections 804 beneath thetreads 802. As such, the reinforcing member 902 is positioned under thegears or wheels, where it is effective both in enhancing durability andreducing the elasticity of the sections 804. These reinforcing members902 can be made from a variety of polymer meshes. Some candidatematerials include, but are not limited to, peek, nylon, or polyester. Inone example, the thickness of these thicker walled sections 804 can beabout 0.012 inches and the reinforcing members 902 can be made of aweave of about 0.002 inch fibers in a 200×200 mesh.

The reinforcing members 902 can be molded into the self-enclosed memberwall by, for example, layering strips of urethane around the reinforcingmaterial inside a mold and then pressing and heating the layers togetherto melt the urethane and flow it in or around the reinforcing material.In the example shown, the reinforcing members 902 are only used underthe treads 802 so the stiffer reinforcing material is not present in thethinner walled web sections 904 outside the gear paths and consequentlydoesn't impact the stiffness of the self-enclosed member 102 in theseareas. It could also be beneficial to have the reinforcing members 902cover a bigger area of the section 804 width, extend into or replace theweb sections 904, or be positioned in a different height in thethickness of the self-enclosed member 102.

Closing Notes:

The present inventors have recognized that (1) it can sometimes beadvantageous to attach the propellable apparatus at a front-end tipportion of a payload, (2) a propellable apparatus having a relativelyshort length (e.g., between about 0.8 inches and about 1.5 inches) doesnot limit articulation of a flexible payload, having a separatelycontrollable articulating capability, an appreciable degree when it ismounted at or near the front-end thereof, (3) drive members made offlexible cable including wrapped filaments allows for adequate flexingwithout reaching unacceptable internal stress levels during rotation,(4) one or more wiper members can be added to the propellable apparatus,such as at one or both apparatus ends, to prevent tissue from engagingwith the apparatus drive mechanism, (5) a tapered member can be added toa back-end of the propellable apparatus to facilitate removal of theapparatus from a cavity or lumen, and (6) one or more reinforcingmembers can be integrated within a self-enclosed member for increaseddurability and rotational use.

The above Detailed Description includes references to the accompanyingdrawings, which form a part of the Detailed Description. The drawingsshow, by way of illustration, specific embodiments in which theinvention can be practiced. These embodiments are also referred toherein as “examples.” Such examples can include elements in addition tothose shown and described. However, the present inventors alsocontemplate examples in which only those elements shown and describedare provided.

All publications, patents, and patent documents referred to in thisdocument are incorporated by reference herein in their entirety, asthough individually incorporated by reference. In the event ofinconsistent usages between this document and those documents soincorporated by reference, the usage in the incorporated referencesshould be considered supplementary to that of this document; forirreconcilable inconsistencies, the usage in this document controls.

In this document, the terms “a” or “an” are used, as is common in patentdocuments, to include one or more than one, independent of any otherinstances or usages of “at least one” or “one or more.” In thisdocument, the term “or” is used to refer to a nonexclusive or, such that“A or B” includes “A but not B,” “B but not A,” and “A and B,” unlessotherwise indicated. In this document, the term “back-end” is used torefer to a portion of a propellable apparatus, which is configured to belocated closer to a cavity or lumen orifice after insertion of theapparatus therein. In contrast, the term “front-end” is used in thisdocument to refer to a portion of the propellable apparatus, which isconfigured to be located farther from the cavity or lumen orifice afterinsertion and which leads the apparatus through the cavity or lumen.

In the appended claims, the terms “including” and “in which” are used asthe plain-English equivalents of the respective terms “comprising” and“wherein.” Also, in the following claims, the terms “including” and“comprising” are open-ended, that is, a system, propellable apparatus,article, or process that includes elements in addition to those listedafter such a term in a claim are still deemed to fall within the scopeof that claim. Moreover, in the following claims, the terms “first,”“second,” and “third,” etc. are used merely as labels, and are notintended to impose numerical requirements on their objects.

The above description is intended to be illustrative, and notrestrictive. For example, the above-described examples (or one or moreaspects thereof) may be used in combination with each other. Otherembodiments can be used, such as by one of ordinary skill in the artupon reviewing the above description. Also, in the above DetailedDescription, various features may be grouped together to streamline thedisclosure. This should not be interpreted as intending that anunclaimed disclosed feature is essential to any claim. Rather, inventivesubject matter may lie in less than all features of a particulardisclosed embodiment. Thus, the following claims are hereby incorporatedinto the Detailed Description, with each claim standing on its own as aseparate embodiment. The scope of the invention should be determinedwith reference to the appended claims, along with the full scope ofequivalents to which such claims are entitled.

The Abstract is provided to comply with 37 C.F.R. §1.72(b), to allow thereader to quickly ascertain the nature of the technical disclosure. Itis submitted with the understanding that it will not be used tointerpret or limit the scope or meaning of the claims.

What is claimed is:
 1. A propellable apparatus attached to a front-endtip portion of an endoscope, the propellable apparatus comprising: aself-enclosed member configured to fit within and partially engage acavity or lumen wall, the self-enclosed member including an innersurface at least partially defining an enclosed region, and an outersurface that turns outwardly to engage the cavity or lumen wall inaddition to turning inward to at least partially encompass a centralregion defining a longitudinal path; an internal drive mechanismengageable with the outer surface of the self-enclosed member, therebyproviding relative movement between the self-enclosed member and thecavity or lumen wall; and a tapered member positioned adjacent aback-end of the self-enclosed member, the tapered member providing asize transition from the back-end of the self-enclosed member to adiametrically smaller outer surface of the endoscope that is insertablewithin the central region, wherein the tapered member is a differentmember than the self-enclosed member.
 2. The propellable apparatus ofclaim 1, wherein the tapered member is actively expandable orcontractible.
 3. The propellable apparatus of claim 2, wherein thetapered member comprises a conically-shaped, actively inflatableballoon.
 4. The propellable apparatus of claim 3, further comprising oneor more tubular members configured to move a fluid into or out of theinflatable balloon for size adjustment.
 5. The propellable apparatus ofclaim 1, wherein the inflatable balloon includes at least one grooveconfigured to house one or more elongate or tubular members.
 6. Thepropellable apparatus of claim 1, wherein the tapered member is coupledadjacent a back-end of the self-enclosed member.
 7. The propellableapparatus of claim 1, further comprising one or more wiper membersincluding an edge configured to press against the outer surface of theself-enclosed member, thereby removing debris as the self-enclosedmember turns.
 8. The propellable apparatus of claim 7, wherein the edgeof the one or more wiper members includes a lubricious coating.
 9. Thepropellable apparatus of claim 1, further comprising an attachmentcoupled in proximity to the self-enclosed member, the attachmentconfigured to couple the endoscope within the central region.
 10. Thepropellable apparatus of claim 9, wherein the endoscope longitudinallyextends from a handle portion to a leading viewing portion, and whereinthe self-enclosed member is attached at the leading viewing portion. 11.The propellable apparatus of claim 1, further comprising one or moredrive members configured to transmit externally-generated power to theinternal drive mechanism, and wherein the one or more drive membersinclude a plurality of filaments wound in at least a first direction anda second direction, the second direction different than the firstdirection.
 12. The propellable apparatus of claim 1, wherein theinternal drive mechanism is configured to receive power in a first formand convert the first form power to a linear impelling power received bythe self-enclosed member.
 13. The propellable apparatus of claim 1,wherein a longitudinal length of the apparatus is less than 1.5 inches.14. The propellable apparatus of claim 1, wherein the tapered member hasa cavity having a substantially same diameter as a diameter of theendoscope inserted into the cavity or lumen.
 15. The propellableapparatus of claim 1, wherein a minimum diameter of the tapered memberat the back-end of the self-enclosed member is substantially a samediameter as a diameter of the endoscope.
 16. The propellable apparatusof claim 1, wherein a clearance exists between the tapered member andthe self-enclosed member.
 17. A propellable apparatus attached to afront-end tip portion of an endoscope, the propellable apparatuscomprising: a self-enclosed member sized and shaped to fit within andengage a cavity or lumen wall, the self-enclosed member including aninner surface at least partially defining an enclosed region, and anouter surface that turns outwardly to engage the cavity or lumen wall inaddition to turning inward to at least partially encompass a centralregion defining a longitudinal path; and at least one reinforcing memberembedded between the inner surface and the outer surface of theself-enclosed member.
 18. The propellable apparatus of claim 17, whereina material of the at least one reinforcing member includes a stiffnessor a toughness greater than a stiffness or toughness of a self-enclosedmember material.
 19. The propellable apparatus of claim 17, furthercomprising an internal drive mechanism engageable with the outer surfaceof the self-enclosed member, thereby providing relative movement betweenthe self-enclosed member and the cavity or lumen wall.
 20. Thepropellable apparatus of claim 19, wherein the internal drive mechanismincludes one or more gears or wheels, and wherein the at least onereinforcing member is positioned in line with a position of the one ormore gears or wheels.
 21. The propellable apparatus of claim 20, whereinthe outer surface of the self-enclosed member includes one or more treadsections configured to engage with the one or more gears or wheels ofthe internal drive mechanism.
 22. The propellable apparatus of claim 17,wherein the at least one reinforcing member includes at least one of apeek, a nylon, a polyester or a urethane material.
 23. The propellableapparatus of claim 17, wherein the at least one reinforcing member ismolded into the self-enclosed member.
 24. A propellable apparatusattached to a front-end tip portion of an endoscope, the propellableapparatus comprising: means for providing an inner surface and an outersurface which move in opposite directions when the apparatus is inmotion, including providing a self-enclosed member defining a centralcavity and having an enclosed region, which is configurable to enterinto and navigate a cavity or lumen; means for providing a tapered sizetransition between the endoscope disposable with the central cavity andan outer surface portion of the self-enclosed member; means forreinforcing a stiffness or toughness of the self-enclosed member; andmeans for propelling the self-enclosed member using the outer surface,wherein the means for providing a tapered size transition is a differentmeans than the means for providing an inner surface and an outersurface.
 25. The propellable apparatus of claim 24, wherein the meansfor reinforcing includes means for decreasing drive force transmissionloss to the self-enclosed member, when powered.